m = 0
a = "it heima is a brand of it cast"
for x in a:
    if x == "a":
        m += 1
print(f"heima cheng xu yuan中有{m}个a")
for x in range(10):
    print(x)
num = 100
a = 0
for x in range(1, num):
    b = x % 2
    if b == 0:
        a += 1
print(f"1到100（不含100）范围内，有{a}个偶数")
# for循环打印九九乘法表
